Now electromagnetic launchers are developed widely and intensively because potentially achievable velocities of bodies in them are rather higher, than it can be received practically in typical thermodynamic guns.
The achievement of very high velocity on electromagnetic launchers will help to solve many military, technical, commercial and scientific problems, such as earth-to-orbit launching of various designs and materials, removal of nuclear waste products, development of new materials and others.
One of the kinds of electromagnetic launchers are coilguns. The coilguns consist of one cylindrical coil or the array of coaxial cylindrical coils located sequentially one after another. The internal diameter of these coils forms the barrel of a launcher. Each coil is connected to the store of high-power energy, such as—inductive store, capacitor store, shock homopolar generator and others. As a rule, the metal cylinder is applied as an armature, which is considered as a short-circuited coil.
The force of interaction between the armature and the coils of the launcher is increasing, if the current flowing in the coils of the launcher and in the armature is increasing. Large values of current and magnetic field in the coil result in many problems. The powerful magnetic field causes the large radial and axial forces that tend to compress the coil in axial direction and to increase the diameter in radial one.
The current flowing in the armature is the current of short circuit and it is used mostly for heating of the armature. It reduces considerably the efficiency of the transformation's electric energy impulse in the kinetic energy of the armature movement.
The impulse of current from the store energy is a high-power impulse and it has small duration. In this connection, there is a problem of creation both high-power and high-speed breakers. In case of sequential switching of the launcher coils it is necessary to solve a problem of synchronous. At each next step of acceleration it is necessary to bring greater impulse of energy to the launcher coil than on one.